We can conceive infinity, vaguely perhaps, as unlimited space, and intemporality as unlimited time, both continuing 'forever'; but, try as we may, we are unable to conceive the absence of space and the absence of time, and we have no words for these conceptual absences.
The term 'eternity', perhaps, should denote an absence of duration which we are unable actually to conceive, but in fact whenever used it merely implies the opposite - 'time without end'. 'Outside space and time' is a vague expression, of poetical character, and 'spaceless' and 'timeless' have no significance that is capable of visualisation.
It is the absence of a concept for a condition in which neither space nor time exists that is significant, for it must necessarily imply that existence as such is dependent on the concept of space-time. It is, of course, evident that this is the case, since all phenomena must be extended spatially and appear to have duration in order to be perceived, but the absence of these terms proves that we have in fact always known it.
The inconceivability of the absence of space-time, the fact that it cannot be thought in the sense of visualised, has a still more profound significance, since nothing objectifiable can be inconceivable.
What, then, is non-objectifiable? Surely any 'thing', any kind of object whatsoever is imaginable? There cannot be anything at all that is not objectifiable, for any and every thing imaginable is thereby conceived in imagination.
What, then, could be inconceivable, what in fact is and must be inconceivable? Only that which is conceiving is itself inconceivable, for only what is conceiving cannot, when conceiving, conceive itself.
It might be maintained that what conceives might conceive itself as an imaginary object, like any other object, in consecutive duration, but conceiving as such, while conceiving, cannot conceive its own conceiving - any more than an eye can see its own looking. Therefore whatever is factually inconceivable can only be the conceiving itself which cannot cognise its own act of cognition.
This demonstrates the dialectic validity of the insight whereby we may apperceive that absence of space-time must necessarily be what we are who cannot conceive it.
It must be evident that what we are is 'conceiving' - for what else could be conceiving what we conceive? And, if there is a phenomenal absence which we cannot conceive, that absence must necessarily be our own absence as what is conceiving.
The phenomenal absence of space-time, being inconceivable, must therefore be our own phenomenal absence as what is conceiving, and - since we cannot conceive our own absence - we must be what space-time is, and space-time must be what noumenally we are.
And that no doubt explains why all that we are, both phenomenally and noumenally, was termed 'mind' by the great Masters of China.
Note: We may assume also that this explains why so very few people are willing to face up to the problem of space-time, why nearly all fight shy of it, decline to discuss it, and just accept it as something inevitable, whether philosophers, the religious, or those who seek 'enlightenment'. Yet surely anyone can see how vitally important it must be, that nothing can be finally understood while that remains unexplained, for it is obvious that whatever is subject to extension in space and to successional duration could not be veritable in itself. The study of space-time in physics may also be the key to the startling fact that so many of the greater physicists have found themselves on or over the borders of metaphysics, and have been brave enough to say so.(© T.J. Gray, 1968)