Telepathy

1 · What it is

Mind to mind

Telepathy is the idea that one person can pick up what another is thinking, seeing or feeling, with no word, sign or glance passing between them. It is the oldest and most familiar claim in psi: the friend who rings just as you think of them, or the twin who knows something is wrong.

In research it has a narrower meaning. A sender attends to a target, a receiver somewhere else tries to describe it, and the result is checked against chance. Everything turns on whether the two are truly cut off from each other.

2 · How people practise it

Sender, receiver, quiet

Most practice works in pairs. The sender holds a picture or a scene in mind; the receiver sits somewhere quiet, often with eyes closed, and describes whatever comes.

Practitioners stress relaxed, open attention rather than effort. The usual advice is to report images and feelings as they arise, to sketch rather than name, and not to guess what the target “should” be, because guesses tend to follow habit.

Some pairs try it in sleep. The sender concentrates on a target during the night, and the receiver writes down their dreams on waking, before learning what the target was.

3 · What the labs tested

The ganzfeld

The best-known test is the ganzfeld, German for “whole field”. The receiver lies back with halved ping-pong balls over the eyes, a soft red light and a gentle hiss in headphones: mild sensory quiet, meant to make faint impressions easier to notice. The sender, in another room, looks at a picture or a clip chosen at random.

Afterwards the receiver sees four options and picks the one that best matches what they experienced. Picking at random would be right one time in four, so chance is 25%. In the automated “autoganzfeld” studies of the 1980s, receivers picked the right one about 32% of the time.

Dream studies began at the Maimonides Medical Center in New York in the 1960s. A 2017 review pooled 50 dream studies from 1966 to 2016 and reported a small effect above chance.

4 · Where it’s contested

The disputed middle

When Julie Milton and Richard Wiseman pooled 30 newer ganzfeld studies, run after the autoganzfeld, they found no overall effect.

A decade later Lance Storm and colleagues pooled 29 studies from 1997 to 2008 and reported hit rates above chance again. Ray Hyman, a long-standing critic, replied in the same journal that the studies were too varied and the effect too inconsistent to count as evidence; the authors answered him.

Supporters read the pooled numbers as a small, real signal. Critics read them as small flaws, flexible analysis and unpublished null results adding up. Neither side yet has the experiment that would settle it.