Spatiality is one of the most interesting facets of van Gogh's works, and it is especially striking in his later paintings. One of these works, Portrait of Dr. Gachet, was done by van Gogh a month before his death, in June of 1890. It is one of two similar portraits, both of which address spacial issues and in which spatiality affects the interpretation of the work. The first is the most interesting spatially. In it, van Gogh breaks the painting into three planes - the table in the foreground, the sitter, and the background, but almost makes the sitter's head a portion of the foreground. The foreground becomes interesting because, in keeping with Novotny's observations in Reflections on a Drawing by van Gogh, it contains extreme details in comparison to the rest of the painting. On the table, van Gogh's direction and flow of paint shifts into small, finely detailed flowers and books. These are also detailed in their significance to the subject, since foxglove has medicinal purposes that relate to the doctor, and the books relate to the melancholy mood of the doctor (and van Gogh himself during this time). It is incredible to compare the extreme detail here (he even placed titles on the books) to the abstract masses of the far background. Besides including such details, the table becomes a representation of most of van Gogh's way of treating space - it is leaning towards us, just so slightly out of standard perspective.
The sitter takes up most of the space in the work, with the artist's trademark flowing, vibrant paint strokes. Again, van Gogh shifts the space to give the illusion of encroaching space. Though the sitter is obviously leaning back in a mood of depression and even lethargy, his head appears as far forward as his front hand, due to the work's warped spatiality. This makes the doctor's hat seem as close to the viewer as the plant in the foreground, and indeed makes our eye confuse the foreground as it moves up to the top of the painting. So, in the bottom half of the work, the table is clearly the foreground with the doctor as the background, but, in the top half, the doctor moves forward and makes the back wall the background, in a sort of optical illusion that keeps our eye moving and flowing throughout the work. The amount of detail adds to this - van Gogh adds details in the hat and face of the sitter to bring them forward. He diminishes fine lines into a single flowing mass in the doctor's body to make it recede. This shifting of background/foreground has the effect of making the forms in the top half of the painting mirror the bottom, creating balance and unity within the work.
Van Gogh's most spatially abstract portion of the painting is the back wall. If the sitter was inside, then what is presumably a blank wall is completely unidentifiable as van Gogh turns it into a flowing, natural mass that seems to place the doctor in front of clouds or water. Even if the sitter was truly outside, the forms are still vague, mountainous masses. The brush strokes of the background are large and help it recede, and also add to the mood and subject matter of the work. By flowing around the form of the doctor's head, the forms seem to become a cloud around him, focusing their energy to him. His face, and thus his expression, becomes the focus point of the work, emphasizing the melancholy mood that is abundant in the painting.
This abstraction and overall distortion is even more visible in the second painting of the doctor. Here, van Gogh has eliminated the books and the detail in the flowers and increased the detail in the face. He also abstracts the background even more, making strong contrasts in the overall forms in the painting.
Another example of van Gogh's manipulation of spatiality can be seen in Old Man in Sorrow (On the Threshold of Eternity), done a month earlier, in April-May of 1890. While this work has a more traditional sense of overall detail, with less contrast between the different sections of the work, it still has an odd sense of perspective. Van Gogh has made the focal point of the perspective the center line of the work, near the man's waist. This means that the viewer is looking down at the floor but up at the man's head and the top of the chair. This gives the painting a sense of moving the eyes upward all at once, an experience that is common in van Gogh's work. The top of the chair seems to be trying to violently detach itself from its legs, twisting the entire chair backwards. Van Gogh has painted the floor almost from where he stands, having seemingly working upward until he ran out of canvas. This also gives us the sense that the man himself is looking downward (even though his eyes are covered in despair), and allows us to easily mimic him, shifting our focus to the floor and increasing the overall sadness of the work.
Finally, in Meadow in the Garden of Saint-Paul Hospital, from May of 1890, van Gogh's amazing spatiality has become the most striking aspect of the work. Van Gogh has managed to make the spatiality instantly address the viewer through his elimination of the horizon, making this painting even more concerned with spatiality than the other works. The entire painting is unified by the flowing plants of the meadow, forming a sort of pattern that is anything but repetitive but flows throughout the work. Here, van Gogh has achieved an ideal sense of unified space by not having to divide the work into any different masses or a foreground and background. There is detail in both the top and the bottom of the work, with the only sense of closeness or distance coming out in van Gogh's varying, exciting brushwork, which flows in every sort of direction. This sense of excitement and movement within an overall mood of calmness and soothing unity is what makes the spatiality work and the painting so striking, as it does in much of van Gogh's work.