(© HKU Press, 1966)
In the photographic analogy, three-dimensional objects are recorded on a two-dimensional plane-surface, light and shade being reversed, and the third dimension being represented by occular perspective. This negative record is then mechanically reversed, thereby producing a two-dimensional positive which represents in perspective the three-dimensional objects recorded.
In the case of sensorial perception/conception the analogy holds good. Four-dimensional apperceptions are translated into three-dimensional concepts, the fourth direction of measurement being represented by the passage of time (duration), also via a negative which is then visualised as a positive, and in both cases a positive image is restored.
For instance an aspect of Suchness (as we have to refer to it, being unable to know anything four-dimensional as such) is translated as a negative concept, and its positive counterpart immediately appears. When this process is reversed the positive is applied to its negative, each annihilating the other, and the resultant phenomenally is the inevitable four-dimensional voidness of 'neither ... nor ...' that cannot be visualised but which noumenally carries a positive implication which nevertheless cannot be a three-dimensional concept.
The most familiar examples of the latter process are the Ch'an series of wu hsin, wu nien, wu wei, etc., mind, thought, action, etc. returned to their negatives no-mind, no-thought, no-action, which mutually negated imply, that is point directly to, the pure four-dimensional non-objectivity that cannot otherwise be described, or be conceived or named without thereby turning it back into a positive concept. This, therefore, can only be referred to, described or indicated in some such terms as 'mind that is no-mind', 'absolute thought', 'action of non-action or non-volitional action' - all perfectly illogical and inacceptable indications within the limits of our dimensionally-restricted powers of conceptualisation.
Note: It may be desirable to remember that each direction of measurement is at right-angles to all others, and that each greater dimension includes all lesser.* Therefore a further and unknown direction, which cannot be visualised from the known, here a fourth from the third, can only be suggested by the 'within' of Jesus, and all we can objectively know of it is that it includes the three that we are able to use.
Mathematics can play symbolically with dimensions ad libitum, but what may thereby be represented is difficult to imagine. In the present example the fourth and all-inclusive is the noumenal where tri-dimensional phenomenality is concerned - as, no doubt, our third would be the noumenal to duo-dimensional beings.
It is evident that the term 'phenomenal' covers all our psycho-physical appearance in three directions of measurement, and that 'noumenality' refers to whatever we may be in a further direction in which the phenomenal is entirely included. That is, therefore, an all-inclusive continuum.
All basic measuring is from here to there; all measurements have a point from which they are made. Ultimately that point is inevitably I, and so whatever I may be.
Therefore I am the point of departure of all dimensions. And as each is at right-angles to all others I must be their mutual centre wherever and whenever that may be.
Finally, since each greater surface or volume embraces all lesser areas I must be the centre of the continuum which all seek to measure.
* Time can be seen to include the three spatial dimensions.