Every thought you focus on is charged with energy, just like if a seed is watered it will germinate into a sprout. Depending on the nature of the thought, it will grow into a dynamic force which will eventually yield the fruits of its vibrational nature.
Your mind sends out energy & frequency based on the dominant nature of the thoughts you focus on consistently. The law of nature is “like attracts like”, just as physical magnets do.
You may argue that north magnets attract south magnets – isn't that opposite? What you have to understand is that the frequency that the north magnet emits is that of the south magnet, hence is why it attracts the south magnet to it.
The advantage you and I have as a human being is we can change the frequency and vibration consciously in our mind, which makes it akin to a dynamic magnet. The more we concentrate on a single thought, the more we magnetise it with our energy and it starts to pull towards us everything with similar vibrations.
Think mostly positive thoughts and your life will reflect positivity internally and externally. Think sad thoughts and you will feel sad and attract people, places, things and circumstances that make you feel sad. Do you see how powerful your mind is? Focus on what you want to magnetise to you.
The law of association plays its part on all levels, including on the thought level. Thought is one of the highest forms of organised energy and through thought, everything else can be influenced.
Hold a strong magnet near a piece of iron and suddenly the iron is charged with the same vibration which turns it into a magnet too. Combine multiple magnets together and the magnetic force of all of them combined cause them to become more powerful and attract things even further away.
The beautiful thing with thought is that distance does not define or limit it. We can be anywhere on earth, in the solar system, in our galaxy, or anywhere in the universe, and our thoughts travel through the ether seeking and harmonising with similar vibrations.
Another way of thinking about it is a specific frequency is played on a speaker. In a row, there are 3 tuning forks. Only one of them starts to vibrate because it resonates and harmonises with the sound coming from the speaker. The rest are seemingly unaffected.
Remember, you attract what you think about most of the time. Your mind is like a magnet, so be conscious of what you want to create in your life.