“Arrr – draw a line on the water, savvy?”
Regarding the five aggregates, allow me to confess a dirty little secret: with the possible exception of form, there is no consensus among Buddhist teachers on the precise definition of each aggregate. The definitions given in the ancient texts do not allow us to draw precise boundaries between aggregates. Hence, Buddhist teachers all have definitions of the five aggregates that are similar, but do not overlap 100%.
For example, most teachers I know place thinking squarely in the “volitional formations” bucket, but one puts most of it in the “perception” bucket. Teachers disagree on whether recognizing the features of an object happens at the level of perception, or consciousness, or both. The definitions of the five aggregates I presented in this series is my own curated collection of what I have learned from a variety of teachers and books. Hence, do not be too alarmed if you find a Buddhist teacher agreeing with only 84% of how I define the aggregates, that teacher probably knows the same dirty little secret I just shared with you, so we’re good.
It turns out that precise boundaries between the mental aggregates cannot actually be drawn. Sāriputta, the Buddha’s wisest disciple, made this point when he stated that, “Sensation, perception and consciousness are conjoined. It is impossible to separate each of these states from the others in order to describe the difference between them.”
There is so much co-dependence and so many feedback loops between the mental aggregates that it is probably impossible to draw clear lines between them. There is a fascinating example that you can immediately verify for yourself. Try this: bring attention to your scalp. Notice tingly sensations in your scalp? Notice those feelings were not there when you were not paying attention? Why? According to neuroscience, we have brain circuits that usually inhibit those tingly sensations, and when we pay attention to the scalp, those circuits are temporarily turned off, which is why you suddenly feel those sensations. This is an example of conscious attention influencing sensation. We usually think of sensation as raw data to be further processed by perception and consciousness, but even sensation itself is subject to feedback loops. There are feedback loops everywhere.
Trying to draw clear boundaries between mental aggregates is like trying to draw precise boundaries between seas. For example, the Coral Sea and the Tasman Sea, located right next to each other, are positionally distinct enough that you can label them separately on a map, but you also cannot draw an exact line and say everything this side of the line is the Coral Sea, and everything that side is the Tasman Sea. Well, you can draw an artificial line in your head, but there are really no natural boundaries between the seas, because at the end of the day, it’s really just one huge continuous body of water. It is the same with the mental aggregates: they are distinct enough that we can roughly label them, but also intertwined enough that there are really no real precise boundaries discernable between them.
In any case, the precise definitions for the aggregates do not really matter. Always remember the first principle: that Buddhism is primarily (or solely) concerned with liberation from all suffering. Suffering relates to the grasping to the five aggregates, and where the exact boundaries of each aggregate lie does not change the nature of the grasping. Hence, we really only need to focus on the aspects of the five aggregates that relate to suffering and liberation from suffering, and those, the Buddha clarified precisely and emphatically.
 Majjhima Nikāya 43.
Featured image by Colin Goh.