Patanjali's yoga sutras

प्रत्यक्षानुमानागमाः प्रमाणानि
pratyakṣa-anumāna-āgamāḥ pramāṇāni

pratyakṣa प्रत्यक्षाय – perception
anumāna अनुमान – inference
āgamāḥ आगम – sacred texts
pramāṇāni प्रमाण – means of attaining knowledge of the truth

Knowledge of the truth is found in sacred texts, but also through direct perception, as well as inference and reflection.

Where can we find evidence of Oneness?

Sacred texts are a great place to start, but it’s written into the patterns of the universe. You can see it in the beauty of nature, in sunrises and sunsets, the moon and the stars, mountains and oceans, and the ones you love. If you are a parent, you know what it’s like to see through the eyes of God. If you’ve ever had a dog, you know what it’s like to be seen through the eyes of God. In the light of Loving Awareness, the divinity of all things is revealed. Anything you can perceive through your five senses can be made holy in this way.

How do we know what’s true?

Ancient and medieval Indian texts, including Akṣapāda Gautama’s Nyaya Sutra (I,i.4), tell us that correct perception has four requirements:

1. It comes thought the senses (indriyarthasannikarsa);
2. It comes direct, not through what you’ve heard from others (avyapadesya);
3. It’s consistent (avyabhicara); and
4. It’s definite, leaving no doubt (vyavasayatmaka).

That said, Akṣapāda Gautama leaves room for divinely revealed knowledge. In addition to ordinary perception (laukika), there’s also extraordinary perception (alaukika), which comes through vividly, just like smell, taste, touch, sound, or sight in the “real world” but it exists only in the inner realm of the mind.

From information collected though perception, inferences can be made. Akṣapāda Gautama names three obvious inferences:

1. Causes have effects (purvavat),
2. Effects have causes (sheshavat), and
3. Correlations suggest a relationship (samanyatodrishta).