For a long time I thought that I shouldn't think during my meditation time.
I'd been taught to either (1) repeat a mantra, thereby keeping thoughts away, or (2) rest in a thoughtless state where the meditator gazes into inner darkness and listens to inner silence, waiting for divine light/sound to appear.
Now, though, I've expanded my meditative horizons, questioning assumptions that I used to accept, well, unquestioningly. Such as, whether it's really desirable to stop thinking while meditating.
Here's my pithy current answer: no. But it's up to the meditator. That's my answer, nobody else's.
I think (there I go again!) it comes down to one's goals.
These are going to be founded on a vision of what life in general, and meditation in particular, are all about. Some religions, mystical practices, and spiritual paths believe that we humans have (or are) a soul that's trapped by our bodies and minds.
So the goal of meditation is to release our pure consciousness from the muck and mire of materiality and mentality, things and thoughts. Detachment from this world supposedly enables the soul to become attached to God, or ethereal divinity.
However, there's another basic way of looking at what meditation is all about: becoming aware that there's no enduring separate entity which can be released from anything.
No soul, no pure consciousness, no Atman that yearns to be united with Brahman. There's only stuff happening, Thoughts are part of that stuff. As is not-thinking and doing other stuff.
So from this perspective it doesn't really matter whether we think during meditation or become thoughtless. If we continue to believe "I'm distinct and separate," the illusion of Enduring Me carries on -- bringing with it the distress of viewing ourselves and life as at odds to some degree or another.
Buddhism is big on this second way of looking at the world. Yet lots of people, me certainly included until recently, feel that thinking is a no-no (or at least to be discouraged) in Buddhist meditation.
In Bodhispaksa's engaging book, "Living as a River," which is based on the Buddhist Six Element Practice tradition, he dispels this notion.
In contemporary insight meditation, when thoughts and images come up, they are to be observed without interference and allowed to pass. The impermanence of thoughts and images is noted, but thoughts and images are not actively cultivated.
...In the Six Element Practice, in contrast to Goenka-style vipassana [insight meditation], we do in fact consciously cultivate the arising of thoughts and images. In other words, we reflect and imagine.
...All this, however, goes against a certain idea of mindfulness, which is that mindfulness involves being aware only of what arises in our present-moment experience, such as the sensations presented to our bodies and any thoughts and feelings that arise naturally.
In the Buddhist tradition, however, the mind is considered to be a sixth sense, so that when we reflect on our internal organs or on the solidity of the earth we are simply paying attention to the present-moment experience of our visual and tactile imagination. Mindfulness can include these things.
...As part of the Six Element Practice, for example, we may repeat the phrase, "This is not me; this is not mine; I am not this." A verse such as this is, as it were, dropped into the mind.
Often when teaching students a technique like this I'll suggest that they imagine they're dropping a stone into a deep well. The verse is released into the depths of the mind, plunging into the waters of the subconscious. Then we simply "listen" for a response.
The verbal thought is simply the first step in a process of reflection that begins in conscious awareness, affects our unconscious mind, and then returns to consciousness in the form of sensations, images, etc.
This makes a lot of scientific sense.
It's well known that most of our brain activity occurs behind the curtain of conscious awareness. So dropping thoughts into the well of our unconscious increases the raw material available for processing into insights, transformations, even "enlightenment."
Thinking about what appears to be real and unreal is going to guide the mind in the direction of reality. It has to. This is how Einstein said he arrived at the general theory of relativity. If it worked for him, I'm more than willing to give it a try.
Having gone to bed in a deep depression, convinced that a coherent theory was forever beyond his grasp, Einstein suddenly had the solution appear "with infinite precision, and with its underlying unity of size, structure, distance, time, space, slowly falling into place piece by piece...[until] like a giant die making an indelible impress, a huge map of the universe outlined itself in one celar vision."
His insights were subsequently expressed in mathematical and verbal form, but they began on a more visceral level. Again, the conscious mind struggles, and the subconscious delivers. Both parts of the process are crucial to the final insight that arises.
(Here's an interesting Seed Magazine article with a lengthy all caps title: "MANY OF BUDDHISM’S CORE TENETS SIGNIFICANTLY OVERLAP WITH FINDINGS FROM MODERN NEUROLOGY AND NEUROSCIENCE. SO HOW DID BUDDHISM COME CLOSE TO GETTING THE BRAIN RIGHT?")