There are three types of comprehensible phenomena (gzhal-bya’i gnas-gsum), differentiated according to how they can be apprehended. A phenomenon is apprehended (rtogs-pa) if it is cognized both correctly and decisively. Thus, the three types of comprehensible phenomena include only existent phenomena (yod-pa).
- Obvious phenomena (mngon-gyur) – those that can be cognized by valid nonconceptual straightforward cognition (mngon-sum tshad-ma). Or they can be specified as those phenomena that be apprehended through the force of personal experience (myong-ba). Examples are the five types of sensory objects – sights, sounds, smells, tastes, and physical and tactile sensations,
- Obscure phenomena (lkog-gyur) – those that cannot be apprehended through the force of personal experience, but can be apprehended through the force of a line of reasoning (rtags). Examples include the presence of fire where there is a smoking chimney, the fact that sound is nonstatic or impermanent, the fact that persons lack of an impossible “soul” (gang-zag-gi bdag-med, selflessness of persons), and the fact that all phenomena are devoid of truly established existence (bden-par ma-grub-pa).
- Extremely obscure phenomena (shin-tu lkog-gyur) – those that can be apprehended through authoritative texts or speech, such as the enlightening words of the Buddha, deemed perfect through the three analyses. Or they are phenomena that can be apprehended through the words of persons who are valid sources of information (tshad-ma’i skyes-bu). Examples include the location of buried treasure, the existence of pure Buddha-realms, and the relation between karmic cause and effect.
Authoritative texts or speech deemed perfect through the three analyses (dpyad-pa gsum-gyis dag-pa’i lung) are those that present topics covering the three types of knowable phenomenon and which:
- In indicating obvious phenomena, are not discredited by valid non-conceptual straightforward cognition
- In indicating obscure phenomena, are not discredited by valid inferential cognition (rjes-dpag tshad-ma)
- In indicating extremely obscure phenomena, neither do its own former and later words contradict each other, nor do valid straightforward cognition, valid inferential cognition, and its own words discredit each other.
We may understand the distinction among the three types of comprehensible phenomena with a simple example:
- Obvious phenomenon – a house on a far mountain, with smoke rising from its chimney – we can see it.
- Obscure phenomenon – fire in the fireplace of that house – we can infer its presence by depending on a line of reasoning: where there is smoke, there is fire.
- Extremely obscure phenomenon – the name of the person living in the house – we need to rely on someone who correctly knows the person’s name in order to know it.
An even more basic example of an extremely obscure phenomenon is our birthday. We needed to rely on our mother, for instance, to know it.