We have discovered about 3800 exoplanets as of July 2018 (archive), and we estimate that around 40 billions are present in our own galaxy.

Someday, we might very well encounter another species with whom we would like to communicate. But what will be their mode of communication? Will we be ready?

Here, I’d like to outline some milestones we need to achieve before we can hope to be able to do so.

1. First Analysis

Aliens, by definitions, are very unlikely to share our appearance, thought processes and values. This implies that many communication means we normally use between humans of different nations cannot apply.

Indeed, what does a hand gesture mean if you don’t have a hand? What’s blue when you can only see infrared?

2. Level 0: with humans of different nations

Undoubtedly the easiest step of all: being able to talk to humans speaking different languages.

This is mostly a solved step thanks to translators, even though not everybody actually speak two or more languages.

A first conclusion is that communication with aliens is likely to happen through a translator of some kind, rather than directly.

3. Level 1: with close animals

Primates, dolphins and whales all seem to have various means to communicate with each other that seem complex, yet reachable.

This is a topic of on-going research, but some promising results already appeared, such as communicating with some primates through sign-language.

Yet, it will still take decades or centuries before we can talk to dolphins, for example.

4. Level 2: with all animals

All other animals that are very different from us pose a different challenge.

Take birds: they tend to live and react within way shorter timelines, such as seeing the world with much shorter time frame, and using singing patterns we don’t understand.

Here lie animals able to experience the world on a different part of the spectrum, such as ultrasound, polarising light, ground vibration, etc.

5. Level 3: with plants and fungi

Animals tend to share our senses, even if they might see different part of the light spectrum, or hear different sounds. At least, we are animals too.

Plants clearly share very little with our senses or our way to see the world.

Movement is just foreign to a plant, and their life usually is on a very different time scale than ours.

Yet, we now know that plants and fungi communicate with each other through chemical signals, rather than sound or signs.

Our understanding level is so limited that we are still discovering new ways by which they communicate with each other, and the meaning we attribute to those messages still is very broad such as "danger".

This is very challenging: talking to a plant implies having physical connection to its roots and leaves, and being able to create thousands of organic compounds in real time, as well as detecting them throughout the organism.

Our current technology doesn’t allow this.

But even if we could, a very broad shift in our point of view and concepts needs to happen. Some concepts may never be mapped to something our own languages can define, as those concept don’t mean anything to us.

6. Conclusion

I propose that the previous scale is a good way to assess our readiness to communicate with a potential alien life-form, should we encounter it:

  • Level 0: communication with humans of different languages

  • Level 1: communication with animals whose communication means are close to ours

  • Level 2: communication with any animals

  • Level 3: communication with plants and fungi

Humanity on a whole is at a level 0.5. Individually, most of the world’s population is at a level 0.

Reaching level 3 doesn’t mean we will be ready, but we would have accomplished the minimum to maximise our chances to communicate with aliens. We could very well meet aliens whose communication systems and concepts lie outside of what human brains could ever hope to understand. In this case, we would have to rely on them to talk to us instead.

There is plenty to be done!