Leonardo da Vinci and Perspective

Leonardo da Vinci (1452–1519) was one of the most important figures in the history of perspective. Artist, scientist, engineer and investigator of vision, Leonardo developed a remarkably broad theory connecting perspective, optics, geometry, light, colour, spatial measurement, visual perception and pictorial representation.

Perspective for Leonardo was far more than a technique for drawing receding lines towards a vanishing point. It was a means of understanding the relationship between the eye, the object, distance, direction, light and the resulting visual appearance. His investigations embraced both the natural perspective through which spatial reality appears to vision and the artificial perspective through which that reality is reconstructed in a picture.

Leonardo studied the point of sight, pyramid of vision, perspective window, picture plane, diminution of size, foreshortening, changing form, vanishing points, horizon line, colour, atmosphere, shadows and reflections. His writings consequently present perspective as both an art of representation and a wider science of visual and spatial relationships.


Leonardo and the Renaissance Development of Perspective

Leonardo did not invent Renaissance linear perspective. Important work had already been undertaken by figures including Filippo Brunelleschi, Leon Battista Alberti, Lorenzo Ghiberti and Piero della Francesca.

Brunelleschi’s perspective demonstrations in the early fifteenth century and Alberti’s written formulation of perspective established the geometrical foundations of the new Renaissance system. Piero della Francesca subsequently developed highly systematic mathematical methods of perspective construction.

Leonardo’s importance lies partly in what he did next. He greatly enlarged the subject, connecting graphical construction with how objects actually appear to the eye and investigating discrepancies between ideal geometrical projection and natural visual appearance.

Perspective became, in his work, not simply a drawing system but a larger investigation into how spatial reality is transformed into visual appearance and how that appearance can be represented.


Leonardo and the Science of Perspective

Leonardo regarded perspective as fundamental to painting because the painter attempts to recreate on a surface the appearances produced when spatial reality is seen from a particular position.

His theory therefore begins with the relationship between:

  • the spatial object or scene;
  • the point of sight or eye-point;
  • the visual rays connecting object and eye;
  • the pyramid of vision;
  • the perspective window or picture plane; and
  • the resulting perspective image.

Leonardo understood that the apparent properties of objects change according to their spatial relationship with the observer. Size, form, colour, contrast and visible detail can all vary with distance, direction, atmosphere and illumination.

Perspective was therefore simultaneously geometrical, optical and visual.



The Pyramid of Vision

One of Leonardo’s most important concepts is the Pyramid of Vision, also called the Pyramid of Sight or visual pyramid.

Visible points on an object can be related to the eye through straight visual rays. Collectively these rays form a pyramidal or conical arrangement whose apex lies at the eye or eye-point.

The geometry establishes the visual angles subtended by objects and their features. These angular relationships are fundamental to the way size, shape and position appear from a particular viewpoint.

If a transparent surface is introduced between the eye and the object, the visual rays intersect that surface. The resulting intersections provide the geometrical basis of a perspective image.

The basic relationship can be represented as:

3-D Object → Visual Rays → Perspective Window → Eye-Point.

This relationship links natural viewing with artificial graphical construction.


The Perspective Window

Leonardo repeatedly explored the principle of the transparent perspective window.

An artist fixes the eye at a chosen point and observes the scene through a transparent glass, veil, net or other intermediate surface. The visible positions of objects can then be traced or transferred onto that surface.

The method establishes the fundamental elements of central perspective:

  • a spatial object or scene;
  • a fixed eye-point;
  • visual or projection rays;
  • an intervening picture plane; and
  • a two-dimensional perspective image.

The perspective window therefore acts as an intersection plane through the pyramid of vision.


Leonardo’s Perspectograph

Leonardo investigated mechanical and geometrical methods for making perspective images accurately. His drawings include the use of a glass, veil, perspective window or perspective net together with a fixed eye-point.

Such a device acts as a perspectograph: an instrument that helps transfer the visible positions of spatial objects onto a picture surface.

One example in the Codex Atlanticus shows the method used in relation to an armillary sphere. The viewer maintains a fixed eye position while the object’s apparent geometry is transferred to the intervening plane.

Perspective drawing machine – sketch by Leonardo da Vinci

This provides a particularly clear demonstration of the relationship between natural vision and graphical perspective. The external scene supplies the visual target; the fixed eye supplies the viewpoint; and the transparent surface converts the spatial relationship into a measurable two-dimensional image.


True or Measured Perspective

Leonardo’s use of the transparent veil or window is also associated with what can be termed true or measured perspective.

Instead of constructing a hypothetical scene entirely through drawing rules, the artist can use an actual spatial target and record its intersections with a defined picture surface from a fixed eye-point.

This creates an especially close connection between:

Physical Spatial Reality → Natural / Visual Perspective → Perspective Window → Graphical Image.

The method illustrates why Leonardo’s work repeatedly crossed the boundary between visual observation, measurement and representation.


Leonardo’s Pyramidal Law

Leonardo described two complementary pyramidal relationships associated with perspective and distance.

1. Pyramid of Vision

The Pyramid of Vision has its apex at the eye and encompasses the spatial objects visible before it. Rays from object points converge towards the viewpoint.

2. Pyramid of Spatial Recession

The Pyramid of Spatial Recession operates in the opposite conceptual direction. Its base is towards the observer and its apex extends towards the horizon. Equal-sized objects positioned progressively farther away occupy successively smaller projected extents.

This second pyramid therefore provides a geometrical model of diminution of size with distance.

Together, the two pyramids connect the visual geometry radiating between object and eye with the spatial recession through which apparent size decreases.


Leonardo and the Size–Distance Relationship

Leonardo investigated the quantitative relationship between object size, distance and visual angle.

Objects of equal physical size normally occupy progressively smaller visual or projected extents as their distance from the observer increases.

This principle is fundamental to the diminution of size characteristic of central and linear perspective.

Leonardo’s importance lies in connecting this geometrical relationship with the larger visual problem of how spatial objects actually appear to the eye.


Leonardo’s Three Branches of Perspective

One of Leonardo’s most significant theoretical contributions was his division of perspective into several different phenomena rather than reducing the entire subject to geometrical convergence.

Volume 1 identifies three major branches of Leonardo’s natural or receding perspective:

  1. Perspective of Form — changes involving size, shape, angle, position, aspect and foreshortening.
  2. Perspective of Colour — changes in colour and contrast as objects recede.
  3. Perspective of Disappearance or Proportion — the progressive loss of visible outline, definition and structural detail with distance.

This classification is strikingly broad. It recognises that recession affects not merely the projected geometry of objects but also their colour, contrast, visibility and apparent structural completeness.


Perspective of Form

Perspective of Form concerns changes in apparent geometrical properties caused by viewing and projection.

These can include:

  • diminution of apparent size;
  • change of apparent shape;
  • aspect;
  • foreshortening;
  • changing angular relationships;
  • position within the visual field;
  • convergence; and
  • other changes produced by spatial recession and viewing direction.

This branch most closely overlaps with what is ordinarily thought of as geometrical or linear perspective, but Leonardo understood it as part of a larger visual system.


Perspective of Colour

Perspective of Colour concerns the way the apparent colour and contrast of objects change with viewing conditions and distance.

Leonardo investigated how atmosphere modifies distant appearance. As the amount of intervening atmosphere increases, distant objects may lose contrast, acquire changes of colour and become visually less distinct.

Within Leonardo’s wider treatment, colour perspective includes relationships associated with aerial or atmospheric perspective, distant colour change, shadows and reflections.

This demonstrates again that perspective is not restricted to the geometry of outlines. The optical properties of the image also change through spatial recession.


Atmospheric or Aerial Perspective

Atmospheric Perspective, also known as Aerial Perspective, is one of the best-known aspects of Leonardo’s study of visual recession.

The atmosphere between observer and object affects the light reaching the eye. With increasing distance, outlines can become less distinct, contrasts can weaken and colours can shift.

Leonardo investigated these effects experimentally and used them artistically to create convincing recession and spatial depth.

This approach connects painting with environmental optics. Space is communicated not merely through line convergence but through the changing optical appearance of objects located at different distances.


Perspective of Disappearance and Diminution of Form

Leonardo also studied the gradual disappearance of visible structure as objects recede.

A distant object may remain physically present while fine details, edges and proportions become increasingly difficult to distinguish.

This can result from several interacting factors, including:

  • reduction of projected size;
  • reduced projection-scale resolution;
  • loss of atmospheric contrast;
  • visual acuity limits; and
  • other optical conditions.

The PRC describes these related effects through concepts including Diminution of Form Perspective, Degradation of Form and Perspective of Disappearance.

Leonardo’s recognition of this phenomenon considerably expands perspective beyond the traditional study of vanishing lines.


Light, Shadow and Chiaroscuro

Leonardo’s investigations of perspective were inseparable from his study of light and shadow.

Light reveals surface orientation, relief, volume and spatial relationships. Shadows provide information about the position of objects, the direction of illumination and the geometry of surfaces.

Leonardo studied luminous and shadow pyramids, reflections and the changing strength and distribution of light upon forms.

His use of chiaroscuro and related modelling of light and shade consequently contributes to the apparent three-dimensionality of painted forms even where no explicit vanishing-line construction is visible.


Sfumato and the Softening of Form

Leonardo’s use of sfumato is also closely connected with his wider understanding of visual and atmospheric perspective.

Rather than defining every boundary through a hard graphical outline, transitions can be softened through subtle changes of tone, colour and contrast.

The technique reflects the fact that natural vision does not always present objects as perfectly bounded geometrical figures. Light, atmosphere, distance and optical conditions can soften or obscure visible edges.

Sfumato therefore demonstrates the movement from purely linear or outline perspective towards a fuller optical representation of visual appearance.


Leonardo and Linear Perspective

Leonardo nevertheless remained a highly accomplished practitioner of Linear Perspective.

Linear perspective constructs a view of three-dimensional spatial reality upon a two-dimensional surface according to a fixed viewpoint and defined projection geometry.

Leonardo employed its principal components:

  • fixed viewpoint;
  • picture plane;
  • visual or projection rays;
  • horizon line;
  • vanishing points;
  • orthogonals;
  • diminution;
  • foreshortening; and
  • geometrical measurement of represented space.

His importance lies partly in recognising that this artificial geometrical system and natural human vision are closely related but not perfectly identical.


Vanishing Points and the Horizon

Leonardo studied the geometrical behaviour of lines and spatial directions within perspective.

Families of parallel lines extending in depth can project towards corresponding vanishing points. The horizon provides an important directional reference for horizontal vanishing relationships associated with the observer’s position and viewing system.

Vanishing geometry is therefore one part of Leonardo’s theory, but only one part. His wider framework also incorporates visual angles, form, colour, atmospheric change and loss of visible detail.


Natural, Artificial and Synthetic Perspective

Leonardo’s writings distinguish between the perspective produced naturally through seeing and the perspective deliberately constructed through graphical methods.

Natural Perspective

Natural Perspective concerns the changing appearance of spatial reality through natural and optical processes. It includes effects involving distance, visual angle, aspect, colour, atmosphere and loss of visible structure.

Artificial Perspective

Artificial Perspective concerns deliberately constructed or represented perspective, including graphical linear-perspective methods used to place three-dimensional spatial relationships upon a picture surface.

Synthetic Perspective

Leonardo also explored combinations in which artificial graphical geometry is adjusted or coordinated with natural visual effects. This relationship can be described as Synthetic Perspective.

In the current PRC taxonomy, Synthetic Perspective and Composite Perspective are closely related but not identical. Composite Perspective formally describes a multi-category arrangement, while Synthetic Perspective describes the resulting perceptually unified combination of perspective processes.

Leonardo’s work is particularly important because he recognised that the theoretically constructed image and the way that image is subsequently seen by an observer must be considered together.


The Visual-Angles Problem

One of the deeper problems recognised by Leonardo concerns the difference between visual angles and flat-plane projection.

The human eye responds to angular relationships centred upon the viewpoint. A linear-perspective picture, however, is conventionally projected onto a flat surface.

These two geometries are closely related but not identical across an unlimited field.

As an object moves laterally away from the central line of sight, its projection onto a flat picture plane can change differently from its angular appearance to the eye.

Leonardo understood that this could create discrepancies between artificial perspective geometry and natural visual appearance.


The Row of Columns Problem

Leonardo considered the difficult problem of several similar round objects or columns arranged laterally across the observer’s field of view.

When projected geometrically onto a flat picture plane, laterally positioned objects can acquire proportions that differ from the way the corresponding completed picture appears when viewed naturally from its intended station point.

The example reveals an important principle: the geometry used to construct an image cannot always be analysed independently of the geometry through which the completed image is subsequently viewed.

This belongs to the larger family of problems now described by the PRC through concepts including lateral distortion, visual angles and discrepancies between graphical and visual perspective.


Ordinary and Special Perspective

The Dictionary of Perspective distinguishes two useful forms associated with Leonardo.

  • Leonardo’s ordinary perspective — his highly developed use of linear perspective, frequently enhanced by atmospheric perspective, colour and sfumato.
  • Leonardo’s special or secret perspective — circumstances in which the geometrical image is deliberately coordinated with the observer’s visual experience and the physical setting.

This second form is particularly important because it recognises the viewer as part of the complete perspective system.


Leonardo and Anamorphic Perspective

Leonardo was also an early investigator of Anamorphic Perspective.

An anamorphic image can appear severely distorted under ordinary viewing conditions but acquire a recognisable or proportioned appearance when viewed from a particular position or through an appropriate geometrical or optical transformation.

Such experiments demonstrate that the geometry placed upon the image surface does not necessarily need to resemble the intended final visual appearance when viewed frontally.

The correct relationship can instead emerge through the interaction of:

Image Geometry + Picture Surface + Viewpoint + Visual Projection.

This makes anamorphosis an important example of Leonardo’s larger interest in the relationship between natural and artificial perspective.


Curved and Non-Planar Picture Surfaces

Leonardo’s investigations were not confined entirely to the conventional flat picture plane.

He also explored perspective effects associated with cylindrical and spherical surfaces and with unusually positioned or inclined picture planes.

This is conceptually important because every different picture-surface geometry creates a different intersection with the larger field or pyramid of visual rays.

The flat Renaissance picture plane is therefore one important perspective configuration rather than the only possible surface upon which a perspective image can be formed.


The Last Supper and Perspective

Leonardo’s The Last Supper, painted c. 1495–1498, is one of the most celebrated examples of Renaissance perspective.

The painted architectural space is organised principally through one-point linear perspective. Major orthogonals converge towards the central region of the composition associated with Christ, creating a powerful geometrical and narrative focus.

But the perspective effect is more sophisticated than a self-contained geometrical construction. The represented architecture interacts with the physical architecture of the refectory in which the work was created.

Real-space and depicted spatial relationships are coordinated so that the painted room can appear to continue the architectural space occupied by the observer.

The work therefore provides an important example of Leonardo’s ability to combine graphical construction, physical setting, viewer position and visual appearance.


Figure 3. Leonardo da Vinci, The Last Supper, c. 1495–1498. The mural employs one-point linear perspective, with the principal orthogonals converging at Christ, while the painted architecture appears to extend the spatial structure of the refectory. Within PRC terminology, this integration of constructed and surrounding space may be interpreted as synthetic perspective.


The Last Supper as Synthetic Perspective

The Last Supper is especially significant when considered through the wider distinction between Natural, Artificial and Synthetic Perspective.

The painted image is artificial and graphical. The physical refectory is real spatial architecture. The completed visual experience occurs when a real observer sees both within one wider perceptual context.

The perspective chain can therefore be expressed as:

Physical Refectory + Graphically Constructed Perspective → Visual Alignment → Apparently Extended Spatial Environment.

From an appropriate viewing relationship, painted and physical space can become perceptually coordinated. This makes the work especially relevant to the modern PRC study of Synthetic Perspective, blended scene geometry and perspective illusion.


Perspective and the Viewer

Leonardo’s work makes clear that a perspective picture should not always be considered independently of the person viewing it.

A perspective construction is produced from a specified eye-point. When the resulting picture is viewed, another geometrical relationship is established between the observer’s eye and the image surface.

The complete system can therefore involve two related stages:

  1. Construction: spatial reality is projected onto the picture surface from a selected viewpoint.
  2. Observation: the completed picture is itself viewed from a physical position.

Where these relationships are coordinated correctly, the picture can produce a particularly convincing spatial illusion.


Leonardo and Motion Perspective

Leonardo also considered the effects of movement upon perspective.

When an observer changes position, the perspective relationships of surrounding objects change continuously. Their projected positions, visible aspects, overlaps and apparent directions alter as the viewpoint moves.

This problem later became fundamental to moving-image photography, cinema, computer graphics and virtual environments.

Leonardo’s interest therefore extended beyond the static geometry of one frozen viewpoint towards the changing relationships produced by an observer moving through spatial reality.


Perspective, Anatomy and the Eye

Leonardo’s extensive anatomical investigations strengthened his interest in the mechanisms of sight.

The eye was not merely a convenient geometrical point within an abstract construction. It was a physical visual organ whose operation Leonardo attempted to understand through anatomy, optics and geometry.

This integration of bodily vision with graphical construction helped establish perspective as a problem involving several distinct but related levels:

  • physical spatial reality;
  • light and optical transmission;
  • the eye and visual geometry;
  • apparent visual form;
  • geometrical abstraction; and
  • graphical representation.

These distinctions remain central to modern studies of perspective and vision.


Perspective as a Bridge between Geometry and Nature

Leonardo’s work demonstrates one of the deepest functions of perspective: it provides a bridge between ideal geometrical Form and observed physical reality.

Geometry reduces complex objects to relationships involving points, lines, angles, planes and solids. Perspective then relates those abstractions to the ways real spatial objects are viewed and represented.

This process operates in both directions:

  • physical objects can be analysed through geometrical forms; and
  • geometrical models can be transformed into convincing representations of physical objects.

Perspective therefore becomes a tool not merely for painting but for measuring, modelling, investigating and communicating spatial reality.


Leonardo’s Notebooks and Treatise on Painting

Leonardo never completed a single final treatise containing his complete theory of perspective. His ideas survive across a vast body of notebook writings and drawings.

Important collections include the Codex Atlanticus, Codex Leicester and Codex Arundel, alongside many other manuscripts.

Material from these writings was later assembled into the Trattato della Pittura, or Treatise on Painting.

The dispersed nature of Leonardo’s writings partly explains why his theory of perspective encompasses such an unusual range of interconnected problems rather than appearing as one simple drawing manual.


Perspective Phenomena Studied by Leonardo

Across his investigations, Leonardo considered a remarkably extensive range of perspective phenomena, including:

  • diminution of size with distance;
  • aspect and changing apparent shape;
  • foreshortening;
  • vanishing points;
  • the horizon line;
  • visual angles;
  • lateral image discrepancies;
  • diminution and degradation of form;
  • loss of visible detail;
  • colour perspective;
  • atmospheric or aerial perspective;
  • contrast change;
  • light and shade;
  • chiaroscuro;
  • reflections;
  • anamorphosis;
  • curved picture surfaces;
  • perspective instruments; and
  • changing perspective produced by movement.

This breadth is why Leonardo’s study of perspective remains important far beyond the history of Renaissance painting.


Leonardo’s Perspective and Modern Imaging

Many problems studied by Leonardo remain fundamental to modern imaging systems.

The fixed eye-point has its counterpart in the camera’s projection centre. The transparent perspective window corresponds conceptually to an image or projection plane. Visual rays correspond to the geometrical rays used in optical modelling and computer graphics.

Modern fields continue to investigate related problems of:

  • viewpoint;
  • field of view;
  • projection geometry;
  • perspective distortion;
  • colour and contrast;
  • resolution;
  • depth;
  • image formation;
  • spatial reconstruction; and
  • matching represented images to visual experience.

These problems now occur in photography, cinema, computer graphics, computer vision, virtual reality and scientific imaging, but their conceptual roots extend deeply into the history of perspective.


Leonardo and Perspective Category Theory

Leonardo’s work is particularly significant when considered through Perspective Category Theory because his investigations repeatedly cross what are now recognised as different categories of perspective.

  • Natural Perspective — the changing appearance of physical spatial reality.
  • Visual Perspective — visible appearance and human visual experience.
  • Optical Perspective — light, visual rays, atmosphere, colour, reflection and image formation.
  • Mathematical Perspective — points, lines, angles, planes, solids, measurement and projection geometry.
  • Graphical Perspective — linear-perspective drawings and paintings.
  • Instrument Perspective — perspective windows, nets and drawing devices.
  • Simulated Perspective — deliberately adjusted or illusory spatial appearances.

Leonardo’s perspective therefore provides an early historical example of the fundamental PRC principle that several perspective categories may participate in the formation and experience of one image.


Why Leonardo da Vinci Matters to the Study of Perspective

Leonardo matters because he refused to separate the construction of perspective pictures from the larger science of how spatial reality appears.

His work connected:

  • art and painting;
  • geometry and mathematics;
  • optics and light;
  • the eye and vision;
  • colour and atmosphere;
  • anatomy;
  • instruments and measurement;
  • physical space;
  • graphical representation; and
  • the position and experience of the observer.

His perspective theory consequently anticipated the modern interdisciplinary problem of understanding the complete chain between spatial reality, optical image formation, visual perception and representation.

This makes Leonardo an especially important historical figure for the wider conception of perspective developed by the Perspective Research Centre.


Leonardo da Vinci and Perspective — Frequently Asked Questions

Why is Leonardo da Vinci important to perspective?

Leonardo developed an unusually broad and scientific theory connecting graphical perspective with vision, optics, geometry, colour, atmosphere, light and the changing appearance of spatial objects.

Did Leonardo da Vinci invent linear perspective?

No. Linear perspective had already been developed during the early Renaissance, particularly through Brunelleschi and Alberti, and was further developed mathematically by figures including Piero della Francesca. Leonardo greatly extended its theory and applications.

What was Leonardo’s Pyramid of Vision?

The Pyramid of Vision is the geometrical arrangement formed by rays connecting visible object points with the eye. Its apex lies at the eye-point, and its intersection with a picture plane can define a perspective image.

What is Leonardo’s perspective window?

The perspective window is a transparent plane, veil, glass or net placed between the viewer and the spatial object. With the eye fixed at one position, the object’s apparent form can be recorded where the visual rays intersect this surface.

What were Leonardo’s three branches of perspective?

They can be described as Perspective of Form, Perspective of Colour and Perspective of Disappearance or Proportion. Together they concern geometrical change, colour and contrast change, and the loss of visible structural detail through recession.

What is Leonardo’s Perspective of Colour?

Perspective of Colour concerns changes in apparent colour and contrast associated with distance, atmosphere, illumination and related optical conditions. It encompasses important aspects of aerial or atmospheric perspective.

What is Leonardo’s Perspective of Disappearance?

It concerns the progressive loss of visible form, outline, proportion and detail as objects recede and their image becomes smaller or less distinct.

What is Leonardo’s Pyramidal Law?

Leonardo described complementary pyramidal relationships involving the Pyramid of Vision, whose rays converge towards the eye, and the Pyramid of Spatial Recession, which represents the progressive reduction in projected size of objects with increasing distance.

How did Leonardo use perspective in The Last Supper?

The Last Supper uses a powerful one-point linear-perspective structure whose principal orthogonals converge towards Christ. The represented architecture is also visually coordinated with the actual architecture of the refectory, creating an apparently extended spatial environment.

What is Leonardo’s Synthetic Perspective?

Synthetic Perspective describes a relationship in which natural or visual perspective and artificial graphical perspective operate together to produce a perceptually unified appearance. Leonardo investigated how constructed perspective could be adjusted or coordinated with the way a completed image is actually viewed.

Did Leonardo study perspective distortion?

Yes. He investigated discrepancies between flat-plane graphical projection and natural visual appearance, including problems involving lateral objects, visual angles and strongly oblique picture surfaces.

Did Leonardo study anamorphic perspective?

Yes. Leonardo was among the early Renaissance investigators of anamorphic effects in which a deliberately transformed image acquires another appearance when viewed or projected under particular geometrical conditions.

Did Leonardo study atmospheric perspective?

Yes. Atmospheric and colour changes with distance were central to his wider theory of perspective and were applied extensively within his painting.

Why is Leonardo’s theory still relevant?

Many of the problems Leonardo investigated—viewpoint, visual angles, projection, image surfaces, colour, atmosphere, apparent form, optical distortion and the relationship between natural vision and representation—remain fundamental to photography, cinema, computer graphics, computer vision, virtual reality and scientific imaging.


Leonardo da Vinci within the Wider History of Perspective

Leonardo stands at a crucial point in the history of perspective. Earlier traditions had established major geometrical and optical principles, while the early Renaissance developed systematic linear-perspective construction. Leonardo brought these developments into a much larger investigation of seeing, imaging and representing spatial reality.

He recognised that geometrical perspective, natural visual appearance, colour, atmosphere, light, form and the physical position of the viewer all interact in determining how space appears.

Perspective in Leonardo’s work therefore becomes both a practical artistic method and a general science of spatial appearance.

This wider conception remains one of his most important contributions: perspective is not merely a system for drawing space, but a framework for understanding the relationship between spatial reality, optics, vision, geometry and the image.