[quote=@Benny]I'm not familiar with the Tide system[/quote]
Basically it's just a way to easily codify a person's personality, depending on their primary motivations. Different driving motivations are linked to [url=https://numenera.gamepedia.com/Tides]certain colours[/url], such as passion, emotion, action, and zeal all being linked to the colour red.

In a way this is similar to the alignment system in [i]D&D[/i], but rather than moralising about whether someone is good or evil it instead makes no such judgment on their motivations, Someone can be passionate in both good and bad ways after all.

The way this affects conversations is that if someone tends to use a personality other than the one they originally chose, they can switch from one colour to another, or even become a blend fo different colours. Hence the name 'Tides', since they can ebb and flow from one situation to the next.

In the game, someone who is a paragon of a certain Tide can use their collected points to help force an issue by accessing Tidal Surges, the use of which varies depending on which Tide the character is promoting within themselves.

For instance, a proponent of the Blue Tide, which represents wisdom, enlightenment, and mysticism might be able to make an outstanding leap of logic, which allows for a breakthrough of scientific knowledge in a moment of great need due to their long years of study and dedication to the gathering of knowledge. In the story this could be a moment where they need to determine how a highly complicated device of unknown origin works within a few seconds to prevent it doing something which may harm the party, and immediately know exactly which button to press to avert disaster.

This can be used as a reward to players who act in a manner fitting to the way they descibed their character, or dedicating themselves wholy to a new personality trait over a long period of time. Or it can be used to reward any specifically important act which would exemplify a certain Tide, for instance a follower of the Gold Tide (charity, sacrifice, and empathy) voluntarily choosing to relinquish an item of great worth to someone in great need of it, despite requiring that item themselves to a greater degree.